Container assembly having a cover cap provided with a pump member to pump out air from a container

A container assembly comprising:

• a hollow casing defining a storing space, and having a top open end and a top opening defined by said top open end for access into said storing space;
• a cover cap mounted detachably and sealingly on said top open end of said hollow casing so as to cover said top opening, said cover cap having a pump-mounting wall portion of a U-shaped cross section that defines a pump-receiving chamber, an inlet formed in said pump-mounting wall portion and in fluid communication with said pump-receiving chamber and said storing space, and a valve-mounting wall portion that extends outwardly from said pump-mounting wall portion and that is formed with an opening which is in fluid communication with said storing space and the atmosphere;
• a pump member disposed movably and sealingly in said pump-receiving chamber and movable toward and away from said inlet so as to vary pressure in the pump-receiving chamber by virtue of change in volume of said pump-receiving chamber, and having an outlet in fluid communication with said pump-receiving chamber and the atmosphere;
• an urging member for urging said pump member away from said inlet;
• a first check valve mounted on said cover cap for closing said inlet, said inlet being opened when pressure in said storing space is greater than that in said pump-receiving chamber, thereby permitting fluid flow from said storing space into said pump-receiving chamber, said inlet being closed by said first check valve when the pressure in said pump-receiving chamber is greater than that in said storing space upon movement of said pump member toward said inlet against urging action of said urging member;
• a second check valve mounted on said pump member for closing said outlet, said outlet being opened when the pressure in said pump-receiving chamber is greater than the atmospheric pressure upon movement of said pump member toward said inlet against the urging action of said urging member, thereby permitting fluid flow from said pump-receiving chamber into the atmosphere, said outlet being closed by said second check valve and said inlet being opened when the pressure in said pump-receiving chamber is less than the atmospheric pressure and the pressure in said storing space upon movement of said pump member away from said inlet by virtue of the urging action of said urging member;
• and
• an air-inlet valve mounted on said cover cap for closing said opening in said cover cap, said air-inlet valve being manually operable to uncover said opening when desired.